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تسجيل مستخدم جديدMultilayer Haldane model
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We propose the model of layered materials, in which each layer is described by the conventional Haldane model, while the inter - layer hopping parameter corresponds to the ABC stacking. We calculate the topological invariant $N_3$ for the resulting model, which is responsible for the conductivity of intrinsic quantum Hall effect. It has been shown that in a certain range of the values of interlayer hopping parameter, the value of $N_3$ is equal to the number of layers multiplied by the topological invariant of each layer. At the same time this value may be calculated using the low energy effective theory.
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We study the Haldane model under strain using a tight-binding approach, and compare the obtained results with the continuum-limit approximation. As in graphene, nonuniform strain leads to a time-reversal preserving pseudo-magnetic field that induces
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